Venus Williams is out with illness and sister Serena arrives with a sore ankle. Those who are hurting include Roger Federer, Rafael Nadal, Caroline Wozniacki and Kim Clijsters.

Venus and Serena Williams share a laugh after an exhibition match in Medellin,… (Raul Arboleda A FP / Getty…)

The Australian Open begins Monday in Melbourne (Sunday in the U.S.) and the injury scorecard is already cluttered before the season's first major.

Serena Williams has already hurt her ankle and Venus Williams didn't make the trip to Australia as she deals with an autoimmune disorder that she disclosed at the 2011 U.S. Open.

Roger Federer has been spotted clutching at his achy back. Rafael Nadal has been seen using a bag with wheels to cart around his tennis gear instead of slinging one over a sore shoulder.

Caroline Wozniacki has had an MRI exam of her wrist and Kim Clijsters missed a practice session, possibly because of a pain in her hip. Tenth-ranked Andrea Petkovic is already gone, having been diagnosed with a stress fracture in her back.

And Ivan Lendl is coaching Andy Murray now. Lendl was an iron man when he played, so maybe it's no coincidence that Murray seems to have no physical complaints.

Novak Djokovic, who finished last year with a 70-6 record and three of the four major titles, including the Australian, is seeded No. 1 in the men's draw and Wozniacki, who is ranked No. 1 in the world but has yet to win a major championship, is the top-seeded woman.

Clijsters, the defending women's champion, is seeded 11th and Serena Williams, who owns five Australian Open titles, is seeded 12th.

If there is a sentimental favorite it might be the 30-year-old Federer whose eight-year streak of winning at least one major championship ended last year.

But after Federer squandered two match points in the fifth set of his semifinal loss at the 2011 U.S. Open to Djokovic, he went on to finish the season with 17 straight wins, including titles at Basel, Switzerland, Paris and the ATP season-ending championships at London.

Federer, though, withdrew from the Qatar Open earlier this month because of a sore back. It was only the second time in his career Federer has withdrawn during an event.

Williams didn't play the Australian Open last year while she was recovering from a series of injuries and illnesses that kept her away from tennis for nearly 12 months.

Her comeback to major tournaments almost ended spectacularly when Williams made it to the finals of the U.S. Open. But she was upset in by Australian Samantha Stosur. Then, in her first tournament since last September, Williams rolled an ankle this month during a match in Brisbane, Australia.

Williams, 30, is in Melbourne, though, and said she is hopeful of playing.

Chris Evert, who is doing commentary for TV coverage that begins at 3:30 p.m. PST Sunday on ESPN2, said she believes both Serena Williams and Federer have at least one more major championship victory run.

"Roger, for sure, you see the motivation," Evert said.

"The thing with Serena is she has to find her motivation. My motivation as I got older was my rivalry with Martina [Navratilova]. Serena hasn't had anyone to motivate her for a while, no real rivalry after Justine Henin retired. That fuels the fire, when you have a competitor."

Hard-hitting 21-year-old Petra Kvitova from the Czech Republic, who won Wimbledon last year and who could take over the No. 1 ranking from Wozniacki by the end of the Australian Open, is healthy and is coming off a breakout season in which she won six tournaments, including her first major at Wimbledon and the season-ending WTA Championships at Istanbul, Turkey.